사용자 지정 태스크에 디버깅 지원 추가

IDTSBreakpointSite 인터페이스 및 BreakpointManager

태스크에서는 정수 ID와 문자열 설명을 매개 변수로 제공하는 BreakpointManager의 CreateBreakpointTarget 메서드를 호출하여 중단점 대상을 만듭니다. 태스크는 코드에서 중단점 대상이 들어 있는 지점에 도달하면 IsBreakpointTargetEnabled 메서드로 중단점 대상을 평가하여 해당 중단점이 설정되어 있는지 확인합니다. true인 경우 태스크에서는 OnBreakpointHit 이벤트를 발생시켜 런타임 엔진에 이를 알립니다.

IDTSBreakpointSite 인터페이스는 태스크를 만들 때 런타임 엔진에서 호출하는 단일 메서드 AcceptBreakpointManager를 정의합니다. 이 메서드는 매개 변수로 BreakpointManager 개체를 제공하며, 이 개체는 태스크에서 중단점을 만들고 관리하는 데 사용됩니다. 태스크에서는 BreakpointManager를 Validate 및 Execute 메서드 실행 중에 사용할 수 있도록 로컬로 저장해야 합니다.

다음 예제 코드에서는 BreakpointManager를 사용하여 중단점 대상을 만드는 방법을 보여 줍니다. 이 예제에서는 OnBreakpointHit 메서드를 호출하여 이벤트를 발생시킵니다.

public void AcceptBreakpointManager( BreakpointManager breakPointManager )
{
   //   Store the breakpoint manager locally.
   this.bpm  = breakPointManager;
}
public override DTSExecResult Execute( Connections connections,
  Variables variables, IDTSComponentEvents events,
  IDTSLogging log, DtsTransaction txn)
{
   //   Create a breakpoint.
   this.bpm.CreateBreakPointTarget( 1 , "A sample breakpoint target." );
...
   if( this.bpm.IsBreakpointTargetEnabled( 1 ) == true )
      events.OnBreakpointHit( this.bpm.GetBreakpointTarget( 1 ) );
}

Public Sub AcceptBreakpointManager(ByVal breakPointManager As BreakpointManager)

   ' Store the breakpoint manager locally.
   Me.bpm  = breakPointManager

End Sub

Public Overrides Function Execute(ByVal connections As Connections, _
  ByVal variables As Variables, ByVal events As IDTSComponentEvents, _
  ByVal log As IDTSLogging, ByVal txn As DtsTransaction) As DTSExecResult

   ' Create a breakpoint.
   Me.bpm.CreateBreakPointTarget(1 , "A sample breakpoint target.")

   If Me.bpm.IsBreakpointTargetEnabled(1) = True Then
      events.OnBreakpointHit(Me.bpm.GetBreakpointTarget(1))
   End If

End Function

IDTSSuspend 인터페이스

IDTSSuspend 인터페이스는 런타임 엔진에서 태스크 실행을 일시 중지하거나 다시 시작할 때 호출하는 메서드를 정의합니다. IDTSSuspend 인터페이스는 IDTSBreakpointSite 인터페이스에 의해 구현되며 이 인터페이스의 Suspend 및 ResumeExecution 메서드는 대개 사용자 지정 태스크에 의해 재정의됩니다. 런타임 엔진은 태스크에서 OnBreakpointHit 이벤트를 받으면 실행 중인 각 태스크의 Suspend 메서드를 호출하여 태스크를 일시 중지하라고 알립니다. 클라이언트가 실행을 다시 시작하면 런타임 엔진에서는 일시 중지된 태스크의 ResumeExecution 메서드를 호출합니다.

태스크 실행을 일시 중지하고 다시 시작하려면 태스크의 실행 스레드를 일시 중지하고 다시 시작해야 합니다. 관리 코드에서는 .NET Framework의 System.Threading 네임스페이스에 있는 ManualResetEvent 클래스를 사용하여 이 작업을 수행합니다.

다음 코드 예제에서는 태스크 실행을 일시 중지하고 다시 시작하는 방법을 보여 줍니다. Execute 메서드는 앞의 코드 예제에서 변경되었으며, 중단점이 발생하면 실행 스레드가 일시 중지됩니다.

private ManualResetEvent m_suspended = new ManualResetEvent( true );
private ManualResetEvent m_canExecute = new ManualResetEvent( true );
private int   m_suspendRequired = 0;
private int   m_debugMode = 0;

public override DTSExecResult Execute( Connections connections, Variables variables, IDTSComponentEvents events, IDTSLogging log, DtsTransaction txn)
{
   // While a task is not executing, it is suspended.  
   // Now that we are executing,
   // change to not suspended.
   ChangeEvent(m_suspended, false);
   
   // Check for a suspend before doing any work, 
   // in case the suspend and execute calls
   // were initiated at virtually the same time.
   CheckAndSuspend();
   CheckAndFireBreakpoint( componentEvents, 1);
}
private void CheckAndSuspend()
{
   // Loop until we can execute.  
   // The loop is required rather than a simple If
   // because there is a time between the return from WaitOne and the
   // reset that we might receive another Suspend call.  
   // Suspend() will see that we are suspended
   // and return.  So we need to rewait.
   while (!m_canExecute.WaitOne(0, false))
   {
      ChangeEvent(m_suspended, true);
      m_canExecute.WaitOne();
      ChangeEvent(m_suspended, false);
   }
}
private void CheckAndFireBreakpoint(IDTSComponentEvents events, int breakpointID)
{
   // If the breakpoint is enabled, fire it.
   if (m_debugMode != 0 &&    this.bpm.IsBreakpointTargetEnabled(breakpointID))
   {
      //   Enter a suspend mode before firing the breakpoint.  
      //   Firing the breakpoint will cause the runtime 
      //   to call Suspend on this task.  
      //   Because we are blocked on the breakpoint, 
      //   we are suspended.
      ChangeEvent(m_suspended, true);
      events.OnBreakpointHit(this.bpm.GetBreakpointTarget(breakpointID));
      ChangeEvent(m_suspended, false);
   }
   // Check for a suspension for two reasons: 
   //   1. If we are at a point where we could fire a breakpoint, 
   //      we are at a valid suspend point.  Even if we didn't hit a
   //      breakpoint, the runtime may have called suspend, 
   //      so check for it.     
   //   2. Between the return from OnBreakpointHit 
   //      and the reset of the event, it is possible to have
   //      received a suspend call from which we returned because 
   //      we were already suspended.  We need to be sure it is okay
   //      to continue executing now.
   CheckAndSuspend();
}
static void ChangeEvent(ManualResetEvent e, bool shouldSet)
{
   bool succeeded;
   if (shouldSet)
      succeeded = e.Set();
   else
      succeeded = e.Reset();

   if (!succeeded)
      throw new Exception("Synchronization object failed.");
            
}
public bool SuspendRequired
{
   get   {return m_suspendRequired != 0;}
   set
   {
      // This lock is also taken by Suspend().  
      // Because it is possible for the package to be
      // suspended and resumed in quick succession, 
      // this property might be set before
      // the actual Suspend() call.  
      // Without the lock, the Suspend() might reset the canExecute
      // event after we set it to abort the suspension.
      lock (this)
      {
         Interlocked.Exchange(ref m_suspendRequired, value ? 1 : 0);
         if (!value)
            ResumeExecution();
      }
   }
}
public void ResumeExecution()
{
   ChangeEvent( m_canExecute,true );
}
public void Suspend()
{
   // This lock is also taken by the set SuspendRequired method.  
   // It prevents this call from overriding an 
   // aborted suspension.  See comments in set SuspendRequired.
   lock (this)
   {
      // If a Suspend is required, do it.
      if (m_suspendRequired != 0)
         ChangeEvent(m_canExecute, false);
   }
   // We can't return from Suspend until the task is "suspended".
   // This can happen one of two ways: 
   // the m_suspended event occurs, indicating that the execute thread
   // has suspended, or the canExecute flag is set, 
   // indicating that a suspend is no longer required.
   WaitHandle [] suspendOperationComplete = {m_suspended, m_canExecute};
   WaitHandle.WaitAny(suspendOperationComplete);
}

Private m_suspended As ManualResetEvent = New ManualResetEvent(True)
Private m_canExecute As ManualResetEvent = New ManualResetEvent(True)
Private m_suspendRequired As Integer = 0
Private m_debugMode As Integer = 0

Public Overrides Function Execute(ByVal connections As Connections, _
ByVal variables As Variables, ByVal events As IDTSComponentEvents, _
ByVal log As IDTSLogging, ByVal txn As DtsTransaction) As DTSExecResult

   ' While a task is not executing it is suspended.  
   ' Now that we are executing,
   ' change to not suspended.
   ChangeEvent(m_suspended, False)

   ' Check for a suspend before doing any work, 
   ' in case the suspend and execute calls
   ' were initiated at virtually the same time.
   CheckAndSuspend()
   CheckAndFireBreakpoint(componentEvents, 1)

End Function

Private Sub CheckAndSuspend()

   ' Loop until we can execute.  
   ' The loop is required rather than a simple if
   ' because there is a time between the return from WaitOne and the
   ' reset that we might receive another Suspend call.  
   ' Suspend() will see that we are suspended
   ' and return.  So we need to rewait.
   Do While Not m_canExecute.WaitOne(0, False)
              ChangeEvent(m_suspended, True)
              m_canExecute.WaitOne()
              ChangeEvent(m_suspended, False)
   Loop

End Sub

Private Sub CheckAndFireBreakpoint(ByVal events As IDTSComponentEvents, _
ByVal breakpointID As Integer)

   ' If the breakpoint is enabled, fire it.
   If m_debugMode <> 0 AndAlso Me.bpm.IsBreakpointTargetEnabled(breakpointID) Then
              '   Enter a suspend mode before firing the breakpoint.  
              '   Firing the breakpoint will cause the runtime 
              '   to call Suspend on this task.  
              '   Because we are blocked on the breakpoint, 
              '   we are suspended.
              ChangeEvent(m_suspended, True)
              events.OnBreakpointHit(Me.bpm.GetBreakpointTarget(breakpointID))
              ChangeEvent(m_suspended, False)
   End If

   ' Check for a suspension for two reasons: 
   '   1. If we are at a point where we could fire a breakpoint, 
   '         we are at a valid suspend point.  Even if we didn't hit a
   '         breakpoint, the runtime may have called suspend, 
   '         so check for it.   
   '   2. Between the return from OnBreakpointHit 
   '         and the reset of the event, it is possible to have
   '         received a suspend call from which we returned because 
   '         we were already suspended.  We need to be sure it is okay
   '         to continue executing now.
   CheckAndSuspend()

End Sub

Shared Sub ChangeEvent(ByVal e As ManualResetEvent, ByVal shouldSet As Boolean)

   Dim succeeded As Boolean
   If shouldSet Then
              succeeded = e.Set()
   Else
              succeeded = e.Reset()
   End If

   If (Not succeeded) Then
              Throw New Exception("Synchronization object failed.")
   End If
 
End Sub

Public Property SuspendRequired() As Boolean
   Get
               Return m_suspendRequired <> 0
  End Get
  Set
    ' This lock is also taken by Suspend().  
     '   Because it is possible for the package to be
     '   suspended and resumed in quick succession, 
     '   this property might be set before
     '   the actual Suspend() call.  
     '   Without the lock, the Suspend() might reset the canExecute
     '   event after we set it to abort the suspension.
              SyncLock Me
                         Interlocked.Exchange(m_suspendRequired,IIf(Value, 1, 0))
                         If (Not Value) Then
                                    ResumeExecution()
                         End If
              End SyncLock
   End Set
End Property

Public Sub ResumeExecution()
   ChangeEvent(m_canExecute,True)
End Sub

Public Sub Suspend()

   ' This lock is also taken by the set SuspendRequired method.  
   ' It prevents this call from overriding an 
   ' aborted suspension.  See comments in set SuspendRequired.
   SyncLock Me
   ' If a Suspend is required, do it.
              If m_suspendRequired <> 0 Then
                         ChangeEvent(m_canExecute, False)
              End If
   End SyncLock
   ' We can't return from Suspend until the task is "suspended".
   ' This can happen one of two ways: 
   ' the m_suspended event occurs, indicating that the execute thread
   ' has suspended, or the canExecute flag is set, 
   ' indicating that a suspend is no longer required.
   Dim suspendOperationComplete As WaitHandle() = {m_suspended, m_canExecute}
   WaitHandle.WaitAny(suspendOperationComplete)

End Sub

참고 항목

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